• Proceedings of the Optical Society of Korea Conference
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• 1990.07a
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• pp.78-86
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• 1990

• Proceedings of the Korean Society of Potoscience Conference
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• 2006.06a
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• pp.37-37
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• 2006

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.8
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• pp.767-773
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• 2008

This paper presents a localization system based on the use of electric compass and tracking IR light source. Digital RGB(Red, Green, Blue)signal of digital CMOS Camera is sent to CPLD which converts the color image to binary image at 30 frames per second. CMOS camera has IR filter and UV filter in front of CMOS cell. The filters cut off above 720nm light source. Binary output data of CPLD is sent to DSP that rapidly tracks the IR light source by moving Camera tilt DC motor. At a robot toward north, electric compass signals and IR light source angles which are used for calculating the data of the location system. Because geomagnetic field is linear in local position, this location system is possible. Finally, it is shown that position error is within ${\pm}1.3cm$ in this system.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.100.1-100.1
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• 2012

태양전지 모듈의 25년 이상 장기간 정상 발전을 위해 태양전지 모듈을 구성하는 부품 소재의 장기 열화메커니즘 연구가 중요시되고 있다. 결정질 및 박막 태양전지 모듈 내 셀을 보호하기 위한 봉지재(Encapsulation)로 다양한 폴리머 재료가 적용되고 있다. 봉지재 부품으로 적용되고 있는 에틸렌 비닐 아세테이트(Ethylene Vinyl Acetate, EVA)는 장기 열화특성 및 내구성 개선 연구가 중요하다. 따라서 EVA를 가속열화하여 열화메커니즘 분석과 25년 보증 내구성을 보유하고 있는지 연구가 필요하다. 본 연구에서는 EVA의 Ultraviolet(UV), 온도 복합 환경스트레스 조건을 적용한 가속시험을 수행하고 장기 열화메커니즘을 분석하였다. 수명 및 손상모델을 이용하여 실환경에서 변화하는 UV와 온도를 일정한 값으로 나타낼 수 있는 UV/온도 가속조건을 설계하였다. 이를 통해 UV/온도 가속조건을 설정하였고 1년 및 25년 동안 EVA에 인가되는 stress와 유사한 양을 인가할 수 있는 시험시간을 결정하였다. 시험 후 전자현미경, AFM, FT-IR, TGA, DSC 등의 분석을 통해 열화메커니즘을 도출하였다.

• Textile Coloration and Finishing
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• v.16 no.1
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• pp.10-17
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• 2004

Wool fabrics were treated with deep UV for 10 to 30min and then dyed with C.I. Acid Yellow 99, C.I, Acid Red 57 and C.I. Acid Blue 62. FT-IR and XPS have been used to prove the chemical composition of wool fiber surfaces. The mechanical property and colorfastness were also studied. The intencities of the peaks of C=O group at $1700^cm^{-1}$ were increased with increasing irradiation time. Relative $O_{1s},\; N_{1s}\; and\; S_{2p}$ intensities increased considerably and oxygen was incorporated in the form of CO and COO on the fiber surface. The dye uptakes of wool fabrics dyed with three acid dyes were proportional to irradiation times and in inversely proportional to irradiation distances. It was found that the tensile strength of wool fabrics were gradually deteriorated with the UV irradiation times. The colorfastness, such as washing, light and rubbing, of UV irradiated wool fabrics dyed with acid dyes were good.

• Textile Coloration and Finishing
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• v.26 no.1
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• pp.53-62
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• 2014

This study examined the dyeability, color fastness and functionality of cotton fabrics dyed with residual parts of cultivated Pteridium aquilinum. UV-Vis absorption spectrum, TLC and FT-IR spectra analysis showed that colorants of Pteridium aquilinum are a mixture of pyrogallol tannin and catechol tannin. Optimum dyeing conditions was confirmed colorant concentration of 500% at $100^{\circ}C$ for 60 minutes. Color fastness followed to washing, rubbing, perspiration and light as 4-5, 5, 4-5(acidic), 3-4(alkaline) and 2, respectively. Deodorization rates of ammonia($NH_3$) and acetic acid ($CH_3COOH$) were analyzed 88.8% and 78.0%. UV protection rate was 94.2% of UV-A and 96.8% of UV-B. UV protection factor(UPF) was 27. Therefore residual parts of cultivated Pteridium aquilinum could be used for a new functional colorant.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.1-6
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• 1997

This study was carried out to identify the three antifungal substances isolated from the culture medium of Pseudomonas sp. A-183 which is antagonistic against Phytophthora capsici. The substance A and B showed positive reactions at the Molish test and Anthrone test, but negative one at the Fehling test, strongly suggesting that both substance A and B had nonreducing sugar frameworks. The substance C only exhibited the phenomenon of the UV induced fluorescence. From the qualitative analysis with the spectroscopic techniques such as UV, Mass, IR and NMR, the substance A and B were known to be composed to sugar and fatty acid, and showed a base peak of 171(m/e). It was identified that substance A was $(2-O-L-rhamnosyl-{\alpha}-L-rhamnosyl-{\beta}-hydroxydecanoyl-{\beta}-hydroxy$ decanoic acid) and the substance B was $({\alpha}-L-rhamnosyl-{\beta}-hydroxydecanoyl-{\beta}-hydroxy$ decanoic acid). The substance C was identified as a phenazine from the results of qualitative analysis with the spectroscopic techniques such as UV, Mass, IR and NMR.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1197-1205
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• 2018

UV protection cosmetics belong to functional cosmetics and contain organic or inorganic UV blocking pigments. The inorganic UV blocking pigments are mainly zinc oxide and titanium dioxide. It is known that inorganic UV blocking pigment has a diameter of 60 to 100 nm and has good blocking ability of UVA and UVB. Also, it has high inactivity against sunlight including UV and is excellent in safety. In addition, it is not absorbed or accumulated on the skin like organic pigments and does not cause skin irritation or allergy. In this study, mica, a plate-shaped inorganic pigment, nanosized titanium dioxide, an UV blocking material, and hydrophobic silica were surface-treated with surfactants. And then, titanium dioxide nanoparticles and silica were physically adsorbed on the mica by non-chemical mutual attraction due to differences in charge. Thereafter, the mica complex was surface-treated with silane to prepare a hydrophobic UV blocking pigment complex. The plate-shaped UV blocking composite improves the cohesiveness of a general nanoparticle material titanium dioxide, enhances UV blocking effect due to uniform dispersion, and can greatly improve dispersion stability in cosmetic formulations by surface treatment with hydrophobic property. The surface charge of the pigment was evaluated by zeta potential. The properties of the UV blocking pigment complex were evaluated by FE-SEM, XRD, FT-IR and UV-VIS.

• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.522-528
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• 2023

In this work, adhesive tapes were prepared for the dicing process in semiconductor manufacturing. Compounds with different numbers of photoreactive groups (f = 1 to 3) were synthesized and incorporated into acrylic copolymers to formulate UV-curable acrylic adhesives. Structural confirmation of the synthesized photoreactive compounds (f = 2 or 3) was performed using nuclear magnetic resonance (NMR) spectroscopy. The introduction of the photoreactive compounds into the acrylic adhesive was accomplished by urethane reactions, and the successful synthesis of the UV-curable acrylic adhesive was verified by Fourier transform infrared (FT-IR) measurements. To evaluate the performance of the adhesive, the peel strength was evaluated before and after UV irradiation using a silicon wafer as a substrate. The adhesive exhibited high peel strength (~2000 gf/25 mm) before UV exposure, which was significantly reduced (~5 gf/25 mm) after UV exposure. Interestingly, the adhesive containing multifunctional photoreactive compounds showed the most significant reduction in peel strength. In addition, surface residue measurements by field emission scanning electron microscopy (FE-SEM) showed minimal surface residue (~0.2%) after UV exposure. Overall, these results contribute to the understanding of the behavior of UV-curable acrylic adhesives and pave the way for potential applications in semiconductor manufacturing processes.

• Korean Journal of Materials Research
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• v.17 no.6
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• pp.323-330
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• 2007

We fabricated thermaly evaporated 10 nmNi/(poly)Si films to investigate the energy saving property of silicides formed by rapid thermal annealing (RTA) at the temperature of $300{\sim}1200^{\circ}C$ for 40 seconds. Moreover, we fabricated $10{\sim}50$ nm-thick ITO/Si films with a rf-sputter as reference films. A four-point tester was used to investigate the sheet resistance. A transmission electron microscope (TEM) and an X-ray diffractometer were used for the determination of cross sectional microstructure and phase changes. A UV-VISNIR and FT-IR (Fourier transform infrared rays spectroscopy) were employed for near-IR and middle-IR absorbance. Through TEM analysis, we confirmed $20{\sim}70nm-thick$ silicide layers formed on the single and polycrystalline silicon substrates. Nickel silicides and ITO films on the single silicon substrates showed almost similar absorbance in near-IR region, while nickel silicides on polycrystalline silicon substrate showed superior absorbance above 850 nm near-IR region to ITO films. Nickel silicide on polycrystalline substrate also showed better absorbance in middle IR region than ITO. Our result implies that nano-thick nickel silicides may have exellent absorbing capacity in near-IR and middle-IR region.